It is a hotly contested competition in which a winner could potentially earn billions of dollars' worth of contracts as NASA’s means of transport. Seeing the potential windfall, a wide range of companies have entered the contest including aerospace giants such as Boeing Co. and privately funded start-ups such as Hawthorne-based Space Exploration Technologies Corp.

But Virgin Galactic wants to give wealthy tourists the chance to circle the Earth as well.

The company says it has taken reservations and deposits from more than 400 people.

“We know that many of those same people, including myself, would also love to take an orbital space trip in the future, so we are putting our weight behind new technologies that could deliver that safely whilst driving down the enormous current costs of manned orbital flight by millions of dollars,” Richard Branson, founder of Virgin Galactic, said in a statement.

Branson did not indicate how much an orbital flight might cost, but added that "today’s announcement is an important step along the way to achieving our ultimate and long term goal of leading an industry which opens up the huge potential of space to everyone."